Next-generation spacecraft will use star trackers and Micro Electro-Mechanical System (MEMS) gyros for attitude determination and control. MEMS gyros are solid-state devices that are used widely in consumer products and are now being adapted for space applications. They are manufactured in large quantities using processes from the semi-conductor industry, are very small, low power, light weight, and inherently low cost. Using MEMS gyros and star trackers can eliminate the need for a high performance Inertial Measurement Unit (IMU) that can be costly and heavy (e.g., $3 million and 45 lbs). The disadvantage of MEMS gyros is that they have much lower accuracy than traditional gyro technologies (e.g., 100 times or greater performance reduction). MEMS gyros may exhibit bias and noise from both uncorrelated and common-mode sources. Common-mode errors may be introduced by fluctuations in power supply voltages, electronics noise or interference between gyro channels. The common-mode errors reduce sensing accuracy thereby limiting the range of applications and the pointing accuracy that can be achieved using MEMS gyros.